The first one can be used to assign one or more local variables in one select.

>I am not sure I understand 100% (I am getting tierd and hungry and I am out of coffee).
>Are you saying that:
>

>DECLARE @Data binary(1024)
>SELECT @Data = Data FROM myTable WHERE Id=2
>

>
>is prefered over
>
>

>DECLARE @Data binary(1024)
>SET @Data = (SELECT Data FROM myTable WHERE Id=2)
>

>?
>
>After using an Id that exists I get the desired result using both approaches. :)
>
>Now to the part I don't understand. The SELECT statement with UNION ALL was that related to this post?
>